Use a vendor directory for repeatable builds - fixes #816

This is using godep to manage the vendor directory.

vendor/github.com/jmespath/go-jmespath/parser.go

@@ -0,0 +1,603 @@
+package jmespath
+
+import (
+	"encoding/json"
+	"fmt"
+	"strconv"
+	"strings"
+)
+
+type astNodeType int
+
+//go:generate stringer -type astNodeType
+const (
+	ASTEmpty astNodeType = iota
+	ASTComparator
+	ASTCurrentNode
+	ASTExpRef
+	ASTFunctionExpression
+	ASTField
+	ASTFilterProjection
+	ASTFlatten
+	ASTIdentity
+	ASTIndex
+	ASTIndexExpression
+	ASTKeyValPair
+	ASTLiteral
+	ASTMultiSelectHash
+	ASTMultiSelectList
+	ASTOrExpression
+	ASTAndExpression
+	ASTNotExpression
+	ASTPipe
+	ASTProjection
+	ASTSubexpression
+	ASTSlice
+	ASTValueProjection
+)
+
+// ASTNode represents the abstract syntax tree of a JMESPath expression.
+type ASTNode struct {
+	nodeType astNodeType
+	value    interface{}
+	children []ASTNode
+}
+
+func (node ASTNode) String() string {
+	return node.PrettyPrint(0)
+}
+
+// PrettyPrint will pretty print the parsed AST.
+// The AST is an implementation detail and this pretty print
+// function is provided as a convenience method to help with
+// debugging.  You should not rely on its output as the internal
+// structure of the AST may change at any time.
+func (node ASTNode) PrettyPrint(indent int) string {
+	spaces := strings.Repeat(" ", indent)
+	output := fmt.Sprintf("%s%s {\n", spaces, node.nodeType)
+	nextIndent := indent + 2
+	if node.value != nil {
+		if converted, ok := node.value.(fmt.Stringer); ok {
+			// Account for things like comparator nodes
+			// that are enums with a String() method.
+			output += fmt.Sprintf("%svalue: %s\n", strings.Repeat(" ", nextIndent), converted.String())
+		} else {
+			output += fmt.Sprintf("%svalue: %#v\n", strings.Repeat(" ", nextIndent), node.value)
+		}
+	}
+	lastIndex := len(node.children)
+	if lastIndex > 0 {
+		output += fmt.Sprintf("%schildren: {\n", strings.Repeat(" ", nextIndent))
+		childIndent := nextIndent + 2
+		for _, elem := range node.children {
+			output += elem.PrettyPrint(childIndent)
+		}
+	}
+	output += fmt.Sprintf("%s}\n", spaces)
+	return output
+}
+
+var bindingPowers = map[tokType]int{
+	tEOF:                0,
+	tUnquotedIdentifier: 0,
+	tQuotedIdentifier:   0,
+	tRbracket:           0,
+	tRparen:             0,
+	tComma:              0,
+	tRbrace:             0,
+	tNumber:             0,
+	tCurrent:            0,
+	tExpref:             0,
+	tColon:              0,
+	tPipe:               1,
+	tOr:                 2,
+	tAnd:                3,
+	tEQ:                 5,
+	tLT:                 5,
+	tLTE:                5,
+	tGT:                 5,
+	tGTE:                5,
+	tNE:                 5,
+	tFlatten:            9,
+	tStar:               20,
+	tFilter:             21,
+	tDot:                40,
+	tNot:                45,
+	tLbrace:             50,
+	tLbracket:           55,
+	tLparen:             60,
+}
+
+// Parser holds state about the current expression being parsed.
+type Parser struct {
+	expression string
+	tokens     []token
+	index      int
+}
+
+// NewParser creates a new JMESPath parser.
+func NewParser() *Parser {
+	p := Parser{}
+	return &p
+}
+
+// Parse will compile a JMESPath expression.
+func (p *Parser) Parse(expression string) (ASTNode, error) {
+	lexer := NewLexer()
+	p.expression = expression
+	p.index = 0
+	tokens, err := lexer.tokenize(expression)
+	if err != nil {
+		return ASTNode{}, err
+	}
+	p.tokens = tokens
+	parsed, err := p.parseExpression(0)
+	if err != nil {
+		return ASTNode{}, err
+	}
+	if p.current() != tEOF {
+		return ASTNode{}, p.syntaxError(fmt.Sprintf(
+			"Unexpected token at the end of the expresssion: %s", p.current()))
+	}
+	return parsed, nil
+}
+
+func (p *Parser) parseExpression(bindingPower int) (ASTNode, error) {
+	var err error
+	leftToken := p.lookaheadToken(0)
+	p.advance()
+	leftNode, err := p.nud(leftToken)
+	if err != nil {
+		return ASTNode{}, err
+	}
+	currentToken := p.current()
+	for bindingPower < bindingPowers[currentToken] {
+		p.advance()
+		leftNode, err = p.led(currentToken, leftNode)
+		if err != nil {
+			return ASTNode{}, err
+		}
+		currentToken = p.current()
+	}
+	return leftNode, nil
+}
+
+func (p *Parser) parseIndexExpression() (ASTNode, error) {
+	if p.lookahead(0) == tColon || p.lookahead(1) == tColon {
+		return p.parseSliceExpression()
+	}
+	indexStr := p.lookaheadToken(0).value
+	parsedInt, err := strconv.Atoi(indexStr)
+	if err != nil {
+		return ASTNode{}, err
+	}
+	indexNode := ASTNode{nodeType: ASTIndex, value: parsedInt}
+	p.advance()
+	if err := p.match(tRbracket); err != nil {
+		return ASTNode{}, err
+	}
+	return indexNode, nil
+}
+
+func (p *Parser) parseSliceExpression() (ASTNode, error) {
+	parts := []*int{nil, nil, nil}
+	index := 0
+	current := p.current()
+	for current != tRbracket && index < 3 {
+		if current == tColon {
+			index++
+			p.advance()
+		} else if current == tNumber {
+			parsedInt, err := strconv.Atoi(p.lookaheadToken(0).value)
+			if err != nil {
+				return ASTNode{}, err
+			}
+			parts[index] = &parsedInt
+			p.advance()
+		} else {
+			return ASTNode{}, p.syntaxError(
+				"Expected tColon or tNumber" + ", received: " + p.current().String())
+		}
+		current = p.current()
+	}
+	if err := p.match(tRbracket); err != nil {
+		return ASTNode{}, err
+	}
+	return ASTNode{
+		nodeType: ASTSlice,
+		value:    parts,
+	}, nil
+}
+
+func (p *Parser) match(tokenType tokType) error {
+	if p.current() == tokenType {
+		p.advance()
+		return nil
+	}
+	return p.syntaxError("Expected " + tokenType.String() + ", received: " + p.current().String())
+}
+
+func (p *Parser) led(tokenType tokType, node ASTNode) (ASTNode, error) {
+	switch tokenType {
+	case tDot:
+		if p.current() != tStar {
+			right, err := p.parseDotRHS(bindingPowers[tDot])
+			return ASTNode{
+				nodeType: ASTSubexpression,
+				children: []ASTNode{node, right},
+			}, err
+		}
+		p.advance()
+		right, err := p.parseProjectionRHS(bindingPowers[tDot])
+		return ASTNode{
+			nodeType: ASTValueProjection,
+			children: []ASTNode{node, right},
+		}, err
+	case tPipe:
+		right, err := p.parseExpression(bindingPowers[tPipe])
+		return ASTNode{nodeType: ASTPipe, children: []ASTNode{node, right}}, err
+	case tOr:
+		right, err := p.parseExpression(bindingPowers[tOr])
+		return ASTNode{nodeType: ASTOrExpression, children: []ASTNode{node, right}}, err
+	case tAnd:
+		right, err := p.parseExpression(bindingPowers[tAnd])
+		return ASTNode{nodeType: ASTAndExpression, children: []ASTNode{node, right}}, err
+	case tLparen:
+		name := node.value
+		var args []ASTNode
+		for p.current() != tRparen {
+			expression, err := p.parseExpression(0)
+			if err != nil {
+				return ASTNode{}, err
+			}
+			if p.current() == tComma {
+				if err := p.match(tComma); err != nil {
+					return ASTNode{}, err
+				}
+			}
+			args = append(args, expression)
+		}
+		if err := p.match(tRparen); err != nil {
+			return ASTNode{}, err
+		}
+		return ASTNode{
+			nodeType: ASTFunctionExpression,
+			value:    name,
+			children: args,
+		}, nil
+	case tFilter:
+		return p.parseFilter(node)
+	case tFlatten:
+		left := ASTNode{nodeType: ASTFlatten, children: []ASTNode{node}}
+		right, err := p.parseProjectionRHS(bindingPowers[tFlatten])
+		return ASTNode{
+			nodeType: ASTProjection,
+			children: []ASTNode{left, right},
+		}, err
+	case tEQ, tNE, tGT, tGTE, tLT, tLTE:
+		right, err := p.parseExpression(bindingPowers[tokenType])
+		if err != nil {
+			return ASTNode{}, err
+		}
+		return ASTNode{
+			nodeType: ASTComparator,
+			value:    tokenType,
+			children: []ASTNode{node, right},
+		}, nil
+	case tLbracket:
+		tokenType := p.current()
+		var right ASTNode
+		var err error
+		if tokenType == tNumber || tokenType == tColon {
+			right, err = p.parseIndexExpression()
+			if err != nil {
+				return ASTNode{}, err
+			}
+			return p.projectIfSlice(node, right)
+		}
+		// Otherwise this is a projection.
+		if err := p.match(tStar); err != nil {
+			return ASTNode{}, err
+		}
+		if err := p.match(tRbracket); err != nil {
+			return ASTNode{}, err
+		}
+		right, err = p.parseProjectionRHS(bindingPowers[tStar])
+		if err != nil {
+			return ASTNode{}, err
+		}
+		return ASTNode{
+			nodeType: ASTProjection,
+			children: []ASTNode{node, right},
+		}, nil
+	}
+	return ASTNode{}, p.syntaxError("Unexpected token: " + tokenType.String())
+}
+
+func (p *Parser) nud(token token) (ASTNode, error) {
+	switch token.tokenType {
+	case tJSONLiteral:
+		var parsed interface{}
+		err := json.Unmarshal([]byte(token.value), &parsed)
+		if err != nil {
+			return ASTNode{}, err
+		}
+		return ASTNode{nodeType: ASTLiteral, value: parsed}, nil
+	case tStringLiteral:
+		return ASTNode{nodeType: ASTLiteral, value: token.value}, nil
+	case tUnquotedIdentifier:
+		return ASTNode{
+			nodeType: ASTField,
+			value:    token.value,
+		}, nil
+	case tQuotedIdentifier:
+		node := ASTNode{nodeType: ASTField, value: token.value}
+		if p.current() == tLparen {
+			return ASTNode{}, p.syntaxErrorToken("Can't have quoted identifier as function name.", token)
+		}
+		return node, nil
+	case tStar:
+		left := ASTNode{nodeType: ASTIdentity}
+		var right ASTNode
+		var err error
+		if p.current() == tRbracket {
+			right = ASTNode{nodeType: ASTIdentity}
+		} else {
+			right, err = p.parseProjectionRHS(bindingPowers[tStar])
+		}
+		return ASTNode{nodeType: ASTValueProjection, children: []ASTNode{left, right}}, err
+	case tFilter:
+		return p.parseFilter(ASTNode{nodeType: ASTIdentity})
+	case tLbrace:
+		return p.parseMultiSelectHash()
+	case tFlatten:
+		left := ASTNode{
+			nodeType: ASTFlatten,
+			children: []ASTNode{{nodeType: ASTIdentity}},
+		}
+		right, err := p.parseProjectionRHS(bindingPowers[tFlatten])
+		if err != nil {
+			return ASTNode{}, err
+		}
+		return ASTNode{nodeType: ASTProjection, children: []ASTNode{left, right}}, nil
+	case tLbracket:
+		tokenType := p.current()
+		//var right ASTNode
+		if tokenType == tNumber || tokenType == tColon {
+			right, err := p.parseIndexExpression()
+			if err != nil {
+				return ASTNode{}, nil
+			}
+			return p.projectIfSlice(ASTNode{nodeType: ASTIdentity}, right)
+		} else if tokenType == tStar && p.lookahead(1) == tRbracket {
+			p.advance()
+			p.advance()
+			right, err := p.parseProjectionRHS(bindingPowers[tStar])
+			if err != nil {
+				return ASTNode{}, err
+			}
+			return ASTNode{
+				nodeType: ASTProjection,
+				children: []ASTNode{{nodeType: ASTIdentity}, right},
+			}, nil
+		} else {
+			return p.parseMultiSelectList()
+		}
+	case tCurrent:
+		return ASTNode{nodeType: ASTCurrentNode}, nil
+	case tExpref:
+		expression, err := p.parseExpression(bindingPowers[tExpref])
+		if err != nil {
+			return ASTNode{}, err
+		}
+		return ASTNode{nodeType: ASTExpRef, children: []ASTNode{expression}}, nil
+	case tNot:
+		expression, err := p.parseExpression(bindingPowers[tNot])
+		if err != nil {
+			return ASTNode{}, err
+		}
+		return ASTNode{nodeType: ASTNotExpression, children: []ASTNode{expression}}, nil
+	case tLparen:
+		expression, err := p.parseExpression(0)
+		if err != nil {
+			return ASTNode{}, err
+		}
+		if err := p.match(tRparen); err != nil {
+			return ASTNode{}, err
+		}
+		return expression, nil
+	case tEOF:
+		return ASTNode{}, p.syntaxErrorToken("Incomplete expression", token)
+	}
+
+	return ASTNode{}, p.syntaxErrorToken("Invalid token: "+token.tokenType.String(), token)
+}
+
+func (p *Parser) parseMultiSelectList() (ASTNode, error) {
+	var expressions []ASTNode
+	for {
+		expression, err := p.parseExpression(0)
+		if err != nil {
+			return ASTNode{}, err
+		}
+		expressions = append(expressions, expression)
+		if p.current() == tRbracket {
+			break
+		}
+		err = p.match(tComma)
+		if err != nil {
+			return ASTNode{}, err
+		}
+	}
+	err := p.match(tRbracket)
+	if err != nil {
+		return ASTNode{}, err
+	}
+	return ASTNode{
+		nodeType: ASTMultiSelectList,
+		children: expressions,
+	}, nil
+}
+
+func (p *Parser) parseMultiSelectHash() (ASTNode, error) {
+	var children []ASTNode
+	for {
+		keyToken := p.lookaheadToken(0)
+		if err := p.match(tUnquotedIdentifier); err != nil {
+			if err := p.match(tQuotedIdentifier); err != nil {
+				return ASTNode{}, p.syntaxError("Expected tQuotedIdentifier or tUnquotedIdentifier")
+			}
+		}
+		keyName := keyToken.value
+		err := p.match(tColon)
+		if err != nil {
+			return ASTNode{}, err
+		}
+		value, err := p.parseExpression(0)
+		if err != nil {
+			return ASTNode{}, err
+		}
+		node := ASTNode{
+			nodeType: ASTKeyValPair,
+			value:    keyName,
+			children: []ASTNode{value},
+		}
+		children = append(children, node)
+		if p.current() == tComma {
+			err := p.match(tComma)
+			if err != nil {
+				return ASTNode{}, nil
+			}
+		} else if p.current() == tRbrace {
+			err := p.match(tRbrace)
+			if err != nil {
+				return ASTNode{}, nil
+			}
+			break
+		}
+	}
+	return ASTNode{
+		nodeType: ASTMultiSelectHash,
+		children: children,
+	}, nil
+}
+
+func (p *Parser) projectIfSlice(left ASTNode, right ASTNode) (ASTNode, error) {
+	indexExpr := ASTNode{
+		nodeType: ASTIndexExpression,
+		children: []ASTNode{left, right},
+	}
+	if right.nodeType == ASTSlice {
+		right, err := p.parseProjectionRHS(bindingPowers[tStar])
+		return ASTNode{
+			nodeType: ASTProjection,
+			children: []ASTNode{indexExpr, right},
+		}, err
+	}
+	return indexExpr, nil
+}
+func (p *Parser) parseFilter(node ASTNode) (ASTNode, error) {
+	var right, condition ASTNode
+	var err error
+	condition, err = p.parseExpression(0)
+	if err != nil {
+		return ASTNode{}, err
+	}
+	if err := p.match(tRbracket); err != nil {
+		return ASTNode{}, err
+	}
+	if p.current() == tFlatten {
+		right = ASTNode{nodeType: ASTIdentity}
+	} else {
+		right, err = p.parseProjectionRHS(bindingPowers[tFilter])
+		if err != nil {
+			return ASTNode{}, err
+		}
+	}
+
+	return ASTNode{
+		nodeType: ASTFilterProjection,
+		children: []ASTNode{node, right, condition},
+	}, nil
+}
+
+func (p *Parser) parseDotRHS(bindingPower int) (ASTNode, error) {
+	lookahead := p.current()
+	if tokensOneOf([]tokType{tQuotedIdentifier, tUnquotedIdentifier, tStar}, lookahead) {
+		return p.parseExpression(bindingPower)
+	} else if lookahead == tLbracket {
+		if err := p.match(tLbracket); err != nil {
+			return ASTNode{}, err
+		}
+		return p.parseMultiSelectList()
+	} else if lookahead == tLbrace {
+		if err := p.match(tLbrace); err != nil {
+			return ASTNode{}, err
+		}
+		return p.parseMultiSelectHash()
+	}
+	return ASTNode{}, p.syntaxError("Expected identifier, lbracket, or lbrace")
+}
+
+func (p *Parser) parseProjectionRHS(bindingPower int) (ASTNode, error) {
+	current := p.current()
+	if bindingPowers[current] < 10 {
+		return ASTNode{nodeType: ASTIdentity}, nil
+	} else if current == tLbracket {
+		return p.parseExpression(bindingPower)
+	} else if current == tFilter {
+		return p.parseExpression(bindingPower)
+	} else if current == tDot {
+		err := p.match(tDot)
+		if err != nil {
+			return ASTNode{}, err
+		}
+		return p.parseDotRHS(bindingPower)
+	} else {
+		return ASTNode{}, p.syntaxError("Error")
+	}
+}
+
+func (p *Parser) lookahead(number int) tokType {
+	return p.lookaheadToken(number).tokenType
+}
+
+func (p *Parser) current() tokType {
+	return p.lookahead(0)
+}
+
+func (p *Parser) lookaheadToken(number int) token {
+	return p.tokens[p.index+number]
+}
+
+func (p *Parser) advance() {
+	p.index++
+}
+
+func tokensOneOf(elements []tokType, token tokType) bool {
+	for _, elem := range elements {
+		if elem == token {
+			return true
+		}
+	}
+	return false
+}
+
+func (p *Parser) syntaxError(msg string) SyntaxError {
+	return SyntaxError{
+		msg:        msg,
+		Expression: p.expression,
+		Offset:     p.lookaheadToken(0).position,
+	}
+}
+
+// Create a SyntaxError based on the provided token.
+// This differs from syntaxError() which creates a SyntaxError
+// based on the current lookahead token.
+func (p *Parser) syntaxErrorToken(msg string, t token) SyntaxError {
+	return SyntaxError{
+		msg:        msg,
+		Expression: p.expression,
+		Offset:     t.position,
+	}
+}